Apparatus for separating materials



J. T. HALZA APPARATUS FOR SEPARATING MATERIALS ,1 Dec. 2, 1952 2SHEETS-SHEET l Filed Oct. 30, 1947 JOHN T. HALZA .A m M M 0 m M H S .I@T M 2 m w E J. N 2 A I R E T A M A m 8 2m N. M m m. H mm l EE T. s my RIl FA J m .I LA* EW S AS. Ro S G ON I w D N .VCH A A U l D WE R .r ,D LDOT Mm ETI-S M M S MNA w ww 7 Mm om M AT L.. CW 2 E P w R W 1 DI 2, nw nD .F

Patented Dec. 2, 1952 UNITED STATES PATENT OFFICE APPARATUS FORSEPARATING MATERIALS .lohn T. Halza, Hazleton, Pa.

Application October 30, 1947, Serial No. 783,101

2 Claims.

My invention has to do particularly with the art of separating materialsof different specific gravities and different coefficients of frictionin a current of water flowing down `an inclined plane `and particularlyover a deep natural refuse bed. The invention relates more particularlyto a method and apparatus for classifying and separating coarse or finecoal (silt) or other minerals in which mixtures of materials of thischaracter are subjected to selective forces `applied to the solids in acurrent of water flowing over a controlled natural refuse bed.

The invention is adapted to the separation of both coarse and fineAnthracite and Bituminous coals as well :as metallic ores, but, for thepurpose of clearness, this method and apparatus will be described as itrelates to the separation of fine coal from its impurities.

In the trough or launder portion of the apparatus, the principle of`alluviation operates to stratify the unsized materials according tospecic gravity differences, while friction becomes effective as thestratified mixture passes over the subsiding surface of the naturalrefuse bed above the refuse compartment, where the lower layer, composedof particles of high density 'and particles of lower density but of ahigh coefficient of friction, is retarded and drawn in. For example,boiler ashes or cinders, some of which Iare of a lower specific gravitythan high-grade coal, but of a higher coeflicient of friction inrelation to coal, as well as bone and slate, will be retarded and drawninto the refuse compartment. ri`hus my method is applicable to manyotherwise valuable Anthracite silt and culm banks or deposits which areseriously poluted with these boiler ashes and cannot economically beseparated with methods available heretofore.

As compared with heretofore known appliances which depend onalluviation, my method shows some improvement in producing stratication,but the chief difference is in the method of removing refuse. Forexample, on a concentrating table the mechanical agitation of the pulpspread over the riiiied plane assists in the process of stratificationand it is also the principal means of removing the refuse in a directionat right angles to the water current but only the heavier constituentsare diverted. Furthermore, concentrating tables have the defect thatthey cannot deal satisfactorly with feeds containing widely variableproportions of refuse to coal. For, if the percentage of refuse drops,coal is lost in it. And, if the percentage of refuse rises abnormally,then the coal is polluted with refuse. In trough washers or launders ofthe endless belt or endless chain type, coal is separated by a currentof water flowing down `an inclined plane land the dirt is removed in adirection opposite to the current of water by means of a belt, drag orscrew conveyor, but such devices are unsatisfactory for separatingboiler ash and other light refuse. Also, endless chain and beltappliances require preliminary classification of feed within relativelyclose sizing ratios, they are of low capacity, and they have the defectof mechanical entanglement of coal with the refuse with no means forcorrecting the defect save by rewashing.

In Rheolaveur washers, as in simple trough washers, stratification iscaused by Ialluviation while the refuse falls through apertures in thebottom of the trough into a series of receptacles through which anupward current of water is admitted into the trough to prevent most ofthe coal particles from being discharged with the refuse. This isdisadvantageous because particles distinctly stratified according todensity differences and flowing over the apertures, are repeatedlydisturbed by this upward current of water. To overcome this tendency, aseries of troughs and, in the treatment of lines, and to a lesser extentwhen treating coarse materials, a great numb-er of such upward currentreceptacles ,are used, and the mixture is thereby unnecessarilysubjected to restratiiication and rewashing. The reason why thesedefects lare present in appliances of this class heretofore known andoperated is largely because they do not employ adequate means fordischarging refuse and intermediate products, or because they operateupon the wrong principle of strata separation and, also, because theylack means for the complete and final separation of the coal or otherproduct of value from the refuse products at the moment whenstratification is complete.

The significance of the defects in prior known appliances and theadvance in the art attributable to my invention, `and the principles onwhich it operates, exemplified by a suitable design of apparatus, willmore fully appear from the description that follows, taken in connectionwith the accompanying drawings. It should be understood, however, thatwhile these specifications describe one mode of practicing the methodand one form of apparatus found most desirable,l the -invention is notlimited thereto, and that it includes other modes of practicing themethod :and other forms and constructions of the apparatus within thescope of the `appended claims.

n the illustrative drawings wherein like charasados? acters representthe same parts -in the several views, Figure l is a side elevation andcross-section of a preferred form of apparatus for practicing theinvention, the section being taken in the line I-I in Figure 2, showingthe materials therein as they appear under the condition of completestratication, and alluvium comprising the two substrata being separatedWhile the low density top strata is in suspension;

Figure 2 is a top plan View of the apparatus shown in Figure l;

Figure 3 is a plan vand Figure 4 a side view, on a larger scale thanthat of Figures l and 2, of the stream-flow float used in my apparatus,which forms ya part of the servo-mechanism (not shown) for regulatingthe speed of the drive mechanism and thereby controlling the sag in thehorizontal plane of the bed surfaces;

Figure 5 is a side elevation and Figure 6 is a front view, on a largerscale than that inv Figures l and 2, of the Weir adjusting mechanism forcontrolling the gradient of the bed;

Figure 7 isv a View similar to Figure 1, illustrating a portion of yamodified form of apparatus provided with two final refuse compartmentsand one middlings compartment for dealing in one operation with anabnormally dirty and difiicult feed; and` Figurel 8 is a diagram or owsheet illustrating the flow or circulation of water and solid materials4as they pass through the form of apparatus shown in Figures 1 and 2,

The illustrated apparatus is adapted to the benei'iciation of both coaland metallic ores, but thedescription which follows will be conned tothe separation of coal as a typical instance of use serving top'res'ent. the essential principles of the invention.`

Referring to Figures 1 to 6.0i the drawings, the apparatus thereinillustratedv comprises an inclined trough orllaunder, Il, which isadjustable in height -at its inflow end (not shown) and is provided atits discharge end with ya hinge I2 and suitable exible side and bottomjoints VI3 connecting it 'to the housing I4 of. the separator, wherebythestreamoffmaterials owing down it is separated into layers by gravityand discharged intothe'receiving chamberxl, which has Ian approximatelylevel bottom I6, ending in `a steep discharge chute I'Ifin the bottom ofwhich are two successiveY openings I8, I9, leading to the refusecompartment 2i! Iand middling compartment-2 I, respectively.

Atth'e. lower endof the discharge chute I'I is.

an adjustable gate or Weir 22 provided with means for raising andlowering rit and holding it in adjustedposition comprising twoverticalgracks 23 (see'Figure 5) secured to the back of the gate andmeshing with a pair of spur gears 24, fixed on a shaft 25 mounted Ainbearings in the side Walls of the housing I4 andprovided with a ratchetdisc 26 onitsouter end and a hand wheel 21. A pawl 28, pivotally mountedon the housing, is provided for engaging the ratchet teeth and retainingthe shaft and gatein vertically adjusted position.

In the apparatusshownin Figure 1 there are two compartments 202I overand beyond which the stream` of stratified materials flows on its Way tothe control weir 22 and into which the heavier materialssink and arewithdrawn. The housing has -a horizontal bottom 29 adjacent to the Weirand a third compartment 30 beyond the Weir into which the coal andlighter portion of the material being separated are discharged and Wherethe water and light refuse and other materials form a suspensoidseparate from the coal. The overow from the compartment 3D passes over afixed wall or weir 3| into the vertical chamber 32 where the Water andlighter materials which are more affected by surface tension or otherfactors than by gravity are separated, the former being drawn offthrough the discharge pipe 33 for reuse and the latter escaping throughthe overflow duct 34. A baille 35 prevents mixing of the clean coal withlighter materials and water leaving the compartment 3B.

The chambers 2l), 2| and 30 are closed at their lower ends by starvalves or vaned drums 36, 31, 38, respectively, which are caused torotate slowly by electric motors 39, 40 and suitable belts or chaingearing 4I, 42, 43, as shown in Figures 1 and 2. The speed of the motor39 which drives the valves 33, 31 controlling the discharge of solidmaterials from the chambers 2, 2 I, is controlled by a oat 45 mounted ona pivoted arm 46 suspended from the top of the housing t4,and-counterbalanced by a weighted lever 41towhich the arm, 46 isVconnected at its free end by a link 48. A dash pot 49 is provided whichis connected to the free end of the armv 41 by arodffor preventingrapidV iiuMctuations-in` the position of the float due to variations inthe amount and character of the material` under treatment. Adjustablestops 5I on the link ,48' engagethe operating arm 52 of the rheostat 53for. turning on-andsoi the current to the motor starting and stoppingswitch 54 of the motor SS'asVdeterrnined by the iioat 45. Y

The speedof the motor 451 whichgoperatesrthe valve38 in the dischargepassage from the chamber `3Ilvis controlled by a float 55 mounted forvertical movement in a tube 51 which projects into the chamber 30 fromabove, the float being suspendedfrom a'counterbalanced lever 58,'by arod 59 uponwhich are adjustable stops Iii]v for actuating the operatingarm 6I ofthe rheostat 6'2 which controls the electric current suppliedtothe motor starting and stopping. switch A(i3.

Electric vibrators Y(i5, 65Lareprovided for shaking the inclined bottomofthe chute Il and -freeing it from heavy particles of slate 4or stonethat tend to collect on any supporting surface not scoured by the streamof water and suspended solid material, as is wellunderstood in this art-The apparatus illustrated in Figure 7 is similar to that shown inFigures 1 and -2 in the general arrangement of the'actuating and controldevices, which areidentied-by the same-reference numbers correspondingto the same parts in-both forms of apparatus,A that illustratedV inFigure 7 having an additional refuse chamber 'I0-posi tioned between thechambers 20 and 2| The chamber 1I) is provided with a discharge'valvecontrolled bythe oat 45 or by an independent float asmay be desirablefor treating some materiali,

My invention avoids the defects of other Washers depending on theprinciple. of alluviation, by treating the materials to be separated inra deep and compact natural .refuse` bed c which automatically subsidesto accommodate freshly introduced refuse which slides down the steeplyinclined end Il' from the v.horizontal bottom I6..of the receivingchamber'Vl5-after rst beingstratifled in the current-of Awater owingYdov'vnthe launder II. Important factors in producingthis result aretheautomatic means and method of removing refuse; the inclination oftheflaun'der. and the change in Width and slope of the launder at theapproach to the refuse bed a; and controlling the depth and contour ofthe bed by means oi the adjustable Weir 22, and the float 45. The heavyrefuse, which is continuously deposited on the subsiding surface of thebed over the final dirt compartment 20 and the middlings compartment 2I, continues to sink at a controlled rate as it is being withdrawn atthe bottom by means of valves 36, 31, which may be of the form shown orin the form of a drum with plane or concave blades xed around itscircumference and rotated in a vertical plane transverse to thedirection of flow over the bed. The stratified materials flowing overcompartments 2|] and 2l, where the actual separation takes place, arenever disturbed beyond hindering the flow of and holding down the lowerlayer of high specific gravity refuse and other materials with a higherfrictional value, while the coal, suspended in the top layer, continuesto go forward rapidly over a protective layer b of bony coal ofintermediate density which concentrates over the middlings compartment 2I, is discharged into a sump (not shown) and returned to the launder Ilby means of a pump or elevator for recirculation in order to build up athick intermediate layer to function as a protective barrier between thelow density materials in the top layers and the high density materialsin the bottom layer a.

The reaction between the lower layer e and the bottom surface It of thei'lrst receiving chamber I5 is suddenly increased because of the abruptreduction in the inclination and a slight widening of the launder troughas it approaches the horizontal bottom surface I6. Most of the suspendedrefuse subsides when it rst comes in contact with the bed over refusecompartment 2! and the remainder, composed largely of particles ofintermediate density, is held down and drawn into the middlingscompartment 2| while the coal and light refuse are held in suspension inlayers c and d and pass over the weir spillway 22. The bed depositedover the horizontal section 2S in front of the Weir 22 is composed verylargely of coal in the area nearest the Weir, while that portion nearestto the middlings compartment 2| containing some coal slowly recedes intothe more rapidly subsiding central portion and passes into the middlingscompartment to be recirculated.

The relatively quiescent condition at the surface of the refuse bed,accompanied by the slight seepage of water through the fine intersticesof the particles, tends to draw in, hold down and entrap the finestparticles of slate or cinders when friction oifers insufficientresistance to their movement, but any such particles discharged with thecoal, are rejected through the classificatory action caused by theturbulence existing over the regulated coal bed in the dewateringcompartment 3Q. The tendency of this slight seepage apparently is tocomplement the forces of friction, and at the same time, to assist inkeeping the bed in a more compact condition. To further accentuate thiscondition the electro magnetic vibrating mechanism 65 is employed underthe steeply inclined approaches to the refuse and middling compartments2d and 2 I. These vibrators 65 constitute a desirable component of myapparatus in so far as they assist in the entrapment of the iinerimpurities which are already in contact with the bed at this point and,more particularly, when the feed is polluted with boiler ashes. Theintense vibration and sharp percussive impact provided by thesevibrators compact the lower layer of high density materials and at thesame time hinder the escape of the low density particles with a highcoeiiicient of friction.

The approach to the heavy refuse opening I8 drops abruptly from thehorizontal section I6 to an inclination of 45. This is desirable inorder to provide a deeper concentration of refuse at this zone of thebed which serves as a protective barrier against the intermediate layerb above and more particularly to prevent coal in the top layers c and dfrom being drawn into the refuse cornpartrnent 25. When the withdrawalof refuse is proportional to the quantity of feed being introduced, anyexcess flows over to the middlings compartment 2 I, where it forms afraction of the recirculating mixture. If the introduction of refusefalls below a predetermined normal quantity, the depth of the refuseaccumulation at this point will remain uniform for the iloat 45 willrespond to the resultant lowering of the bed at this point and actua-tethe servomechanism to slow up the motor 39 controlling rotation of thedischarge valves Se, 3T; and thus by means of the up and down variationsof the bed level between the two refuse compartments the apparatusmaintains the desired balance between the refuse being withdrawn andthat beign introduced. This streamiiow float l5 can actuate any suitableservomechanism, preferably in a direct current system producing fastresponse and accurate speed control of the motor S9 and having fullpower available at a high starting torque and ruiming load at all speedsof the rotor drive.

When a stoppage of the feed occurs all discharge ports are automaticallyshut off. The cavity or depression maintained between the two ref usecompartments is kept within certain predetermined limits. If thisdepression were too deep, swirling counter-currents would form and causea contamination of the products particularly if the feed volume islight, coal being trapped among the refuse and dirt among the coal. Itis, therefore, to eliminate this condition that the feed is maintainedat full capacity and the float is placed between the two refusecompartments, the rate of discharge 0f the middlings and the heavyrefuse compartments being equal. The variations in the level of the bedin this reference zone are under close control. When the extreme highand low limits are reached the circuit is opened or closed, while `themovement of the lever arm actuated by the oat within these limits variesthe speed of the motor. Thus, the refuse concentration over compartment29 is maintained at a uniform and unvarying depth regardless of variations and irregularities of feed in quality Products of intermediatedensity, together with some high and some low specific gravitymaterials, are withdrawn by the middlings compartment 2l to berecirculated, incidentally for rewashing but primarily to build up athick layer b of intermediate density between the coal and dirt strata.The bed contour within the housing is given a steeper inclination thanin the launder by lowering the adjustable Weir 2B in order to acceleratethe velocity of the coal or other value product in the upper strata cand d as it ows over the receding intermediate layer into the coalcompartment Sil. In this compartment, the coal bed is held at apredetermined level by the cylindrical icat 55, the lower end of whichprojects below the float chamber 51, and which actuates a lever arm andmercury switch to open and close a circuit at adjustable points on thefloat rod. The coal bed is maintained at a level suiiciently below thebaiiie 35 to permit the dirty water to 'overflow `the Weir 3l into thewater compartment 32 from where it is drawn olf by pipe 33 into a waterrecirculating sump of a suitable type. If a blockage of the compartmentat the ope ing to pipe 33 occurs, the overflow pipe 3d which connectswith the recirculating sump draws off the surplus water until nor-malconditions are restored. The product discharged from the coal port Vbythe rotor valve 33 can be collected by any suitable means such as aconveyor belt, elevator or gravity, and fed to the classifying andrinsing screens. VThe products from all discharge ports, if nes arebeing treated, can also be collected into suitable sumps and conveyedhydraulically.

The general control of the apparatus according to my invention iseffected by adjusting the elevation of the weir 22 at the spillway intochamber 3i! to determine the gradient of the refuse bed; a float 55automatically controls the level of the coal bed by measuring theirvariations within predetermined high and low limits and through suitableservo-mechanism regulates the speed of the discharge valve motor 40; alaunder hinged in sections having water-tight joints 9, to permit theinclination to be adjusted in order to increase or decrease the velocityof the current as demanded lby volume or quality of feed; and a leveland speed control servomechanism actuated by a stream-flow float 45 tocontrol, within predetermined limits, the depression depth in the refusebed over the middlings compartment. The Ipurpose of varying orregulating Ithe inclination of the plane of the refuse bed is toincrease or decrease frictional resistance overits surface. The correctgradient is determined by the character ofthe feed and the viscousdensity of the water. Any suitable hinged joint with a Iwater-tightrubber or other flexible seal at the junction lof the launder I l andthe horizontal approach I6 to the refuse bed, enables `adjustment of thelaunder inclination. The launder is elevated at the feeder end by anysuitable means.

The correct inclination of the launder is also determined by experimentwith the type of feed to be treated and the density of the medium to beused. The inclination of the launder is given 'a somewhat higher valuefor a highly heterogeneous feed and a lower value for one of a morehomogeneous character or quality. These values also determine thevelocity of the current and the capacity of the apparatus. If aparticular feed to be processed contains a greater proportion of refuseto coal, apparatus with a second refuse compartment 'I0 (Figure '7)ahead of the middlings compartment 2l would be preferred. Since thestratification is never disturbed before final separation is attempted,the introduction of a second refuse compartment to form a threestage4unit facilitates sepa-ration of a very dirty and diicult feed in onecontinuous operation without resort to rewashing.

In employing my apparatus for the separation of coal from itsimpurities, the coal mixture is preferably vunsized when subjected tothe separation treatment and sized after treatment.

The invention is not restricted to the details of construction or formsof apparatus illustrated.

W hat is claimed is:

1. Apparatus for separating coal particles from boiler ash, ybone coal,slate and other impurities found in culm banks which comprises a launderhaving means for adjusting its slope, an elongated separator into whichsaid launder discharges, said separator having a portion of its 'bottomsloping in `the direction of flow and provided with at least twoopenings through its bottom, a chamber beneath each said opening`provided with a discharge valve, a float in said separator above saidopenings, said float being adjustable vto ride on the heavy refuse bedcarried by vthe discharge lfrom said launder, means controlled by theposition of said oat for governing the discharge passing through saidvalves, means for recirculating the discharge through on'eiof saidvalves to the feed to the launder, a weir in said separator and a coalsettling chamber rinto which the discharge over said Weir passes, saidsettling chamber being provided with a discharge valve, a second floatin said settling chamber, said second float being adjustable to ride onthe coal bed in said settling chamber, and 'means controlled by Atheposition of said second iioat for governing the discharge passingthrough said coal settling chamber discharge valve.

2. Apparatus for separating coal particles from boiler ash, bone coal,sla-te and other impurities found in culm banks which comprises alaunder having means for adjusting its slope, an elongated separatorinto which said launder discharges, said separator having a portion ofits bottom sloping in the direction of flow and provided with at leasttwo openings through its bottom, a chamber beneath each of saidopenings, said oat being adjustable to ride on the heavy refuse bedcarried by the discharge from said launder, means controlled by theposition of said float for governing the discharge passing through saidvalves, means for recirculating the discharge through one of said valvesto the feed launder, an adjustable weir in said separator and a coalsettling chamber into which the discharge over said Weir passes, saidsettling chamber being provided with a discharge Valve, a second floatin said settling chamber, said second float being adjustable to ride onthe coal bed in said settling chamber, and means controlled by theposition of said second float for governing the discharge passingthrough said coal settling chamber discharge valve, and a frothseparating chamber into which water and light refuse from said coalsettling chamber passes, said froth separating chamber being providedwith separate outlets for water and light refuse.

JOHN T. HALZA.

REFERENCES CITED The following references `are of vrecord in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,065,288 Whitten June 17, 19131,561,919 France Nov. 17, 1925 1,897,545 Bird Feb. 14, 1933 1,906,916Mitchell May 2, 1933 2,074,977 Bird Mar. 23, 1937 2,132,380 Attwood Oct.11, 1938 2,211,895 Hayois Aug. 20, 1940 2,286,067 Davis June 9, 19422,312,865 Bird Mar. ,2, 1943 FOREIGN PATENTS Number Country Date 40,685France May .10, 1932 v840,665 `France Jan. 23, 1939

